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2003 K1200GT Cold Start Problem

I owned a brand new 2004 K1200GT back in late '04. Sold it after 3 years or so.
The 2004 had a cold start issue that was completely resolved under warranty with a CPU swap as I recall.

My, new to me 2003, has a cold start issue. Same as the 2004. Starts, establishes a sub 1,000 rpm idle and stalls, restarts and does same, will not take any throttle without bogging/stalling for 20-30 seconds. Affter a half minute or so, runs fine.

Original owner provided service history. Cold start recall repair was done back in 2004.

Does anyone know/remember the #s of the good and bad control units or have any other thoughts on the subject?

I did disconnect the battery and performed the throttle position reset procedure.
No help.

I find that if after starting, I blip the throttle a bit, it stumbles, nearly stalls, but then recovers and achieves the higher rpm that my throttle blip initiated. Each moment that passes and I have kept the fire lit, engine is warming and chances of settling into a steady idle improve.

Runs fine after about 20 seconds or so of fussing around.

I should add that this is a cold start problem in cold ambient temps....
50F and below. The colder the ambient temp, the more pronounced the problem.

I would check for faults in the Motronic either with GS-911 or BMW's GT1. If nothing is found there, I would check fuel pressure and ignition timing, the plug wire resistance. You may need to adjust the throttle potentiometer. That is an awful job, so don't go there unless absolutely neccesary. Either diagnosis system will tell you the throttle pot is defective, and they're usually wrong.

I am running the older control unit by choice, and have no stalling problems in any temperature I am willing to ride, drawing the line at 30 degrees.

The improved control unit has the numbers 166 at the end of its label.

If you start the bike and leave the throttle alone for a few seconds, will it continue to run, or does it stall?

Actually, I think the new units bore a number ending in 266--I had mine replace on the '04GT shortly after I bought it new. You have to remove the ECU in order to see the numbers. You can also check the number with a GS911 if you have access to one.

OP here...
Well, so far, 3 different CPU#s are posted here in response to my original question.

I'm sure you all mean well...
Confusing though.

I found this thread from another forum whislt searching the INTRANET "2003 K1200GT cold start"
If the link works, there is a post with a couple u-tube videos that demonstrate the condition.http://www.i-bmw.com/showthread.php?t=33445
Then, what's this about installing a 296 chip in the 166 control unit as a lower cost solution to solve the problem?
Might have to contact that fella...

I'll keep at it.

I know for sure that the cold start issue on my 2004 GT was completely corrected by a Control Unit swap under BMW warranty back in '04/'05.

I have a bike made 04/03 with the ECU with the last number 166 on it. Only time a idle problem at start up was when it was like 15-25 F degrees. Then I have to give it some throttle once fired up till it runs cleanly.

I did have some idle hunt begin. At a stoplight once warm, it would sometimes dip from 1100 to 900 for a second or two then come back up. During a long light of 2 minutes or so, it might do this 3 or 4 times.

When I switched the chips to the Rhinewest, upon start up it runs a bit faster at first, 1500 rpms then settles back to idle. Overall the bike was smoother and a bit better gas mileage.

The other issue that might affect things would be some vacuum leaks. My bike had picked up some minor irregularities and over time found the distribution rail cracked, the throttle bodies' rubber all cracked and those were fixed.

There was still a bit of unsettledness, (just not running quite right like it had been) and found coilpack voltages were not good as well as plug wires needed replacing. Those things have it running I think the best it has since I have had it.

Pulled a "166" out of the RS and installed the ECU from above. Noticeably better.
Maybe not quite as good as a "296", but still better. Can rev the bike immediately after
start-up (major improvement), and I notice a bit better throttle response when riding.

Will know more after I put a few miles on the bike. Not bad for a $75 investment.